The series revolves around the eponymous Digimon creatures and their human "Tamers", who both serve as player and non-player characters depending on the game. Gameplay focuses on battles between Digimon, with Tamers present or otherwise. The creatures can "Digivolve" back and forth between several evolutionary forms.[2] Due to gameplay similarities, Digimon has experienced rivalry with the equally successful Pokémon series. However, it has maintained a dedicated fanbase.[3]